With a liner hung to the surrounding tubular it is desirable to do a cement integrity test by setting a packer on top of the liner hanger to isolate the liner hanger for a pressure test on the casing above. One potential problem with doing this is that the differential on the test packer transfers load to the seal on the liner hanger and can overstress the liner that is at the same time supported off the casing just below the liner hanger seal. In essence the liner hanger slips support the hanger seal and the test packer pushes down on the liner hanger seal against the support of the liner hanger slips with the result being a potential overstress of the top of the liner in the vicinity of the liner hanger seal.
To address this problem in the past the test packers being provided also had slips to dig into the casing to take the differential pressure load while isolating the load from the liner hanger seal. However, these packers generally operated mechanically with a j-slot in combination with drag blocks. The presence of drag blocks precluded reciprocation or rotation of the string supporting the test packer during subsequent operations because the drag block would rub the casing wall and erode the wall.
What is needed and provided by the present invention is a way to keep the test packer retracted for run in. The packer is hydraulically unlocked so that subsequent setting down force will extend the slips and set the packer seal for the test packer. The cement integrity test can then be run with the slips set in the casing so that the differential pressure load is not applied to the seal in the liner hanger. This protects the liner hanger from damage by overstressing. At the end of that test the string is picked up to stretch out the packer and to place locking dogs in alignment with a locking groove inside the outer housing. A second ball is dropped on a seat to break a restraint and move a sleeve to put the dogs in a secured position in the respective groove in the housing. This can be done with pressure simply moving a sleeve down or a return spring moving a sleeve up after initial downward movement breaks a shear device. At that point the string from the surface can be rotated or reciprocated as completion fluids are spotted. A circulation sub can have a port open above the test packer to continue with circulation or for reverse circulation while bypassing the liner. Those skilled in the art will more readily understand the present invention from a review of the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the appended claims.